Disable hypermedia in actuator endpoints by default

This change permanently removes links from the endpoints that return
arrays or collections, and also disables them in the rest of the
endpoints (except /actuator) by default.

Fixes gh-4616

spring-boot-actuator/src/main/java/org/springframework/boot/actuate/autoconfigure/EndpointWebMvcHypermediaManagementContextConfiguration.java

@@ -18,6 +18,7 @@ package org.springframework.boot.actuate.autoconfigure;
 
 import java.io.IOException;
 import java.lang.reflect.Type;
+import java.util.Collection;
 import java.util.List;
 import java.util.Map;
 import java.util.concurrent.ConcurrentHashMap;
@@ -205,10 +206,9 @@ public class EndpointWebMvcHypermediaManagementContextConfiguration {
 	 * Controller advice that adds links to the existing Actuator endpoints. By default
 	 * all the top-level resources are enhanced with a "self" link. Those resources that
 	 * could not be enhanced (e.g. "/env/{name}") because their values are "primitive" are
-	 * ignored. Those that have values of type Collection (e.g. /trace) are transformed in
-	 * to maps, and the original collection value is added with a key equal to the
-	 * endpoint name.
+	 * ignored.
 	 */
+	@ConditionalOnProperty(prefix = "endpoints.hypermedia", name = "enabled", matchIfMissing = false)
 	@ControllerAdvice(assignableTypes = MvcEndpoint.class)
 	public static class MvcEndpointAdvice implements ResponseBodyAdvice<Object> {
 
@@ -245,6 +245,10 @@ public class EndpointWebMvcHypermediaManagementContextConfiguration {
 				// Assume it already was handled or it already has its links
 				return body;
 			}
+			if (body instanceof Collection || body.getClass().isArray()) {
+				// We can't add links to a collection without wrapping it
+				return body;
+			}
 			HttpMessageConverter<Object> converter = findConverter(selectedConverterType,
 					selectedContentType);
 			if (converter == null || isHypermediaDisabled(returnType)) {

spring-boot-actuator/src/test/java/org/springframework/boot/actuate/endpoint/mvc/HalBrowserMvcEndpointDisabledIntegrationTests.java

@@ -0,0 +1,109 @@
+/*
+ * Copyright 2012-2015 the original author or authors.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package org.springframework.boot.actuate.endpoint.mvc;
+
+import org.junit.Before;
+import org.junit.Test;
+import org.junit.runner.RunWith;
+
+import org.springframework.beans.factory.annotation.Autowired;
+import org.springframework.boot.SpringApplication;
+import org.springframework.boot.actuate.autoconfigure.MinimalActuatorHypermediaApplication;
+import org.springframework.boot.actuate.endpoint.mvc.HalBrowserMvcEndpointDisabledIntegrationTests.SpringBootHypermediaApplication;
+import org.springframework.boot.test.SpringApplicationConfiguration;
+import org.springframework.context.annotation.Configuration;
+import org.springframework.http.MediaType;
+import org.springframework.test.annotation.DirtiesContext;
+import org.springframework.test.context.junit4.SpringJUnit4ClassRunner;
+import org.springframework.test.context.web.WebAppConfiguration;
+import org.springframework.test.web.servlet.MockMvc;
+import org.springframework.test.web.servlet.MvcResult;
+import org.springframework.test.web.servlet.setup.MockMvcBuilders;
+import org.springframework.web.context.WebApplicationContext;
+
+import static org.junit.Assert.assertEquals;
+import static org.springframework.test.web.servlet.request.MockMvcRequestBuilders.get;
+import static org.springframework.test.web.servlet.result.MockMvcResultMatchers.header;
+import static org.springframework.test.web.servlet.result.MockMvcResultMatchers.jsonPath;
+import static org.springframework.test.web.servlet.result.MockMvcResultMatchers.status;
+
+/**
+ * Integration tests for {@link HalBrowserMvcEndpoint}
+ *
+ * @author Dave Syer
+ * @author Andy Wilkinson
+ */
+@RunWith(SpringJUnit4ClassRunner.class)
+@SpringApplicationConfiguration(SpringBootHypermediaApplication.class)
+@WebAppConfiguration
+@DirtiesContext
+public class HalBrowserMvcEndpointDisabledIntegrationTests {
+
+	@Autowired
+	private WebApplicationContext context;
+
+	@Autowired
+	private MvcEndpoints mvcEndpoints;
+
+	private MockMvc mockMvc;
+
+	@Before
+	public void setUp() {
+		this.mockMvc = MockMvcBuilders.webAppContextSetup(this.context).build();
+	}
+
+	@Test
+	public void linksOnActuator() throws Exception {
+		this.mockMvc.perform(get("/actuator").accept(MediaType.APPLICATION_JSON))
+				.andExpect(status().isOk()).andExpect(jsonPath("$._links").exists())
+				.andExpect(header().doesNotExist("cache-control"));
+	}
+
+	@Test
+	public void browser() throws Exception {
+		MvcResult response = this.mockMvc
+				.perform(get("/actuator/").accept(MediaType.TEXT_HTML))
+				.andExpect(status().isOk()).andReturn();
+		assertEquals("/actuator/browser.html", response.getResponse().getForwardedUrl());
+	}
+
+	@Test
+	public void endpointsDoNotHaveLinks() throws Exception {
+		for (MvcEndpoint endpoint : this.mvcEndpoints.getEndpoints()) {
+			String path = endpoint.getPath();
+			if ("/actuator".equals(path)) {
+				continue;
+			}
+			path = path.length() > 0 ? path : "/";
+			this.mockMvc.perform(get(path).accept(MediaType.APPLICATION_JSON))
+					.andExpect(status().isOk())
+					.andExpect(jsonPath("$._links").doesNotExist());
+		}
+	}
+
+	@MinimalActuatorHypermediaApplication
+	@Configuration
+	public static class SpringBootHypermediaApplication {
+
+		public static void main(String[] args) {
+			SpringApplication.run(SpringBootHypermediaApplication.class,
+					new String[] { "--endpoints.hypermedia.enabled=false" });
+		}
+
+	}
+
+}

spring-boot-actuator/src/test/java/org/springframework/boot/actuate/endpoint/mvc/HalBrowserMvcEndpointManagementContextPathIntegrationTests.java

@@ -93,10 +93,8 @@ public class HalBrowserMvcEndpointManagementContextPathIntegrationTests {
 	@Test
 	public void trace() throws Exception {
 		this.mockMvc.perform(get("/admin/trace").accept(MediaType.APPLICATION_JSON))
-				.andExpect(status().isOk())
-				.andExpect(jsonPath("$._links.self.href")
-						.value("http://localhost/admin/trace"))
-				.andExpect(jsonPath("$.content").isArray());
+				.andExpect(status().isOk()).andExpect(jsonPath("$._links").doesNotExist())
+				.andExpect(jsonPath("$").isArray());
 	}
 
 	@Test

spring-boot-actuator/src/test/java/org/springframework/boot/actuate/endpoint/mvc/HalBrowserMvcEndpointVanillaIntegrationTests.java

@@ -16,6 +16,10 @@
 
 package org.springframework.boot.actuate.endpoint.mvc;
 
+import java.util.Arrays;
+import java.util.HashSet;
+import java.util.Set;
+
 import org.junit.Before;
 import org.junit.Test;
 import org.junit.runner.RunWith;
@@ -27,6 +31,7 @@ import org.springframework.boot.test.SpringApplicationConfiguration;
 import org.springframework.context.annotation.Configuration;
 import org.springframework.http.MediaType;
 import org.springframework.test.annotation.DirtiesContext;
+import org.springframework.test.context.TestPropertySource;
 import org.springframework.test.context.junit4.SpringJUnit4ClassRunner;
 import org.springframework.test.context.web.WebAppConfiguration;
 import org.springframework.test.web.servlet.MockMvc;
@@ -50,6 +55,7 @@ import static org.springframework.test.web.servlet.result.MockMvcResultMatchers.
 @SpringApplicationConfiguration(SpringBootHypermediaApplication.class)
 @WebAppConfiguration
 @DirtiesContext
+@TestPropertySource(properties = "endpoints.hypermedia.enabled=true")
 public class HalBrowserMvcEndpointVanillaIntegrationTests {
 
 	@Autowired
@@ -83,9 +89,8 @@ public class HalBrowserMvcEndpointVanillaIntegrationTests {
 	@Test
 	public void trace() throws Exception {
 		this.mockMvc.perform(get("/trace").accept(MediaType.APPLICATION_JSON))
-				.andExpect(status().isOk())
-				.andExpect(jsonPath("$._links.self.href").value("http://localhost/trace"))
-				.andExpect(jsonPath("$.content").isArray());
+				.andExpect(status().isOk()).andExpect(jsonPath("$._links").doesNotExist())
+				.andExpect(jsonPath("$").isArray());
 	}
 
 	@Test
@@ -111,8 +116,13 @@ public class HalBrowserMvcEndpointVanillaIntegrationTests {
 
 	@Test
 	public void endpointsEachHaveSelf() throws Exception {
+		Set<String> collections = new HashSet<String>(
+				Arrays.asList("/trace", "/beans", "/dump"));
 		for (MvcEndpoint endpoint : this.mvcEndpoints.getEndpoints()) {
 			String path = endpoint.getPath();
+			if (collections.contains(path)) {
+				continue;
+			}
 			path = path.length() > 0 ? path : "/";
 			this.mockMvc.perform(get(path).accept(MediaType.APPLICATION_JSON))
 					.andExpect(status().isOk()).andExpect(jsonPath("$._links.self.href")

spring-boot-actuator/src/test/java/org/springframework/boot/actuate/endpoint/mvc/MvcEndpointIntegrationTests.java

@@ -70,7 +70,7 @@ public class MvcEndpointIntegrationTests {
 		this.context = new AnnotationConfigWebApplicationContext();
 		this.context.register(DefaultConfiguration.class);
 		MockMvc mockMvc = createMockMvc();
-		mockMvc.perform(get("/beans")).andExpect(content().string(startsWith("{\"")));
+		mockMvc.perform(get("/mappings")).andExpect(content().string(startsWith("{\"")));
 	}
 
 	@Test
@@ -199,7 +199,7 @@ public class MvcEndpointIntegrationTests {
 		EnvironmentTestUtils.addEnvironment(this.context,
 				"spring.jackson.serialization.indent-output:true");
 		MockMvc mockMvc = createMockMvc();
-		mockMvc.perform(get("/beans"))
+		mockMvc.perform(get("/mappings"))
 				.andExpect(content().string(startsWith("{" + LINE_SEPARATOR)));
 	}
 

spring-boot-samples/spring-boot-sample-hypermedia-gson/src/test/java/sample/hypermedia/gson/SampleHypermediaGsonApplicationTests.java

@@ -37,7 +37,7 @@ import static org.springframework.test.web.servlet.result.MockMvcResultMatchers.
 @RunWith(SpringJUnit4ClassRunner.class)
 @SpringApplicationConfiguration(SampleHypermediaGsonApplication.class)
 @WebAppConfiguration
-@TestPropertySource(properties = "endpoints.health.sensitive: false")
+@TestPropertySource(properties = "endpoints.hypermedia.enabled: true")
 public class SampleHypermediaGsonApplicationTests {
 
 	@Autowired
@@ -61,9 +61,8 @@ public class SampleHypermediaGsonApplicationTests {
 	@Test
 	public void trace() throws Exception {
 		this.mockMvc.perform(get("/trace").accept(MediaType.APPLICATION_JSON))
-				.andExpect(status().isOk())
-				.andExpect(jsonPath("$.links[0].href").value("http://localhost/trace"))
-				.andExpect(jsonPath("$.content").isArray());
+				.andExpect(status().isOk()).andExpect(jsonPath("$.links").doesNotExist())
+				.andExpect(jsonPath("$").isArray());
 	}
 
 	@Test

spring-boot-samples/spring-boot-sample-hypermedia-jpa/src/test/java/sample/hypermedia/jpa/SampleHypermediaJpaApplicationIntegrationTests.java

@@ -61,7 +61,8 @@ public class SampleHypermediaJpaApplicationIntegrationTests {
 	@Test
 	public void health() throws Exception {
 		this.mockMvc.perform(get("/admin/health").accept(MediaType.APPLICATION_JSON))
-				.andExpect(status().isOk()).andExpect(jsonPath("$._links").exists());
+				.andExpect(status().isOk())
+				.andExpect(jsonPath("$._links").doesNotExist());
 	}
 
 	@Test